Huge Pre-Stonehenge Complex Found via "Crop Circles"

Given away by strange, crop circle-like formations seen from the air, a huge prehistoric ceremonial complex discovered in southern England has taken archaeologists by surprise.

A thousand years older than nearby Stonehenge, the site includes the remains of wooden temples and two massive, 6,000-year-old tombs that are among "Britain's first architecture," according to archaeologist Helen Wickstead, leader of the Damerham Archaeology Project.

For such a site to have lain hidden for so long is "completely amazing," said Wickstead, of Kingston University in London.

Archaeologist Joshua Pollard, who was not involved in the find, agreed. The discovery is "remarkable," he said, given the decades of intense archaeological attention to the greater Stonehenge region.

"I think everybody assumed such monument complexes were known about or had already been discovered," added Pollard, a co-leader of the Stonehenge Riverside Project, which is funded in part by the National Geographic Society. (The National Geographic Society owns National Geographic News.)

Six-Thousand-Year-Old Tombs

At the 500-acre (200-hectare) site, outlines of the structures were spotted "etched" into farmland near the village of Damerham, some 15 miles (24 kilometers) from Stonehenge (Damerham map).

Discovered during a routine aerial survey by English Heritage, the U.K. government's historic-preservation agency, the "crop circles" are the results of buried archaeological structures interfering with plant growth. True crop circles are vast designs created by flattening crops.

The central features are two great tombs topped by massive mounds—made shorter by centuries of plowing—called long barrows. The larger of the two tombs is 70 meters (230 feet) long.

Estimated at 6,000 years old, based on the dates of similar tombs around the United Kingdom, the long barrows are also the oldest elements of the complex.

Such oblong burial mounds are very rare finds, and are the country's earliest known architectural form, Wickstead said. The last full-scale long barrow excavation was in the 1950s, she added.